Re: [PATCH] firmware: stratix10-svc: Fix a resource leak in an error handling path

[Richard Gong]

Hi Jaillet,

Thanks!

On 5/21/21 1:22 PM, Christophe JAILLET wrote:
> If an error occurs after a successful 'kfifo_alloc()' call, it must be
> undone by a corresponding 'kfifo_free()' call, as already done in the
> remove function.
>
> While at it, move the 'platform_device_put()' call to this new error
> handling path and explicitly return 0 in the success path.
>
> Fixes: b5dc75c915cd ("firmware: stratix10-svc: extend svc to support new RSU features")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> ---
>   drivers/firmware/stratix10-svc.c | 22 +++++++++++++++-------
>   1 file changed, 15 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
> index 3aa489dba30a..2a7687911c09 100644
> --- a/drivers/firmware/stratix10-svc.c
> +++ b/drivers/firmware/stratix10-svc.c
> @@ -1034,24 +1034,32 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
>   
>   	/* add svc client device(s) */
>   	svc = devm_kzalloc(dev, sizeof(*svc), GFP_KERNEL);
> -	if (!svc)
> -		return -ENOMEM;
> +	if (!svc) {
> +		ret = -ENOMEM;
> +		goto err_free_kfifo;
> +	}
>   
>   	svc->stratix10_svc_rsu = platform_device_alloc(STRATIX10_RSU, 0);
>   	if (!svc->stratix10_svc_rsu) {
>   		dev_err(dev, "failed to allocate %s device\n", STRATIX10_RSU);
> -		return -ENOMEM;
> +		ret = -ENOMEM;
> +		goto err_free_kfifo;
>   	}
>   
>   	ret = platform_device_add(svc->stratix10_svc_rsu);
> -	if (ret) {
> -		platform_device_put(svc->stratix10_svc_rsu);
> -		return ret;
> -	}
> +	if (ret)
> +		goto err_put_device;
> +
>   	dev_set_drvdata(dev, svc);
>   
>   	pr_info("Intel Service Layer Driver Initialized\n");
>   
> +	return 0;
> +
> +err_put_device:
> +	platform_device_put(svc->stratix10_svc_rsu);
> +err_free_kfifo:
> +	kfifo_free(&controller->svc_fifo);

Need for the allocated memory pool as well,
	if (ctrl->genpool)
                gen_pool_destroy(ctrl->genpool);

Rename err_free_kfifo to include both.

>   	return ret;
>   }
>   

Regards,
Richard